I'd stick with the sand filter. Although larger than the alternatives, its maintainance schedule is a breeze, and unlike cartridge filters, you don't need to replace your sand every few months.
My experience with DE filters is limited to my mother's pool. It had one when she bought the place, and didn't seem to work all that great - there was always silt in places where there shouldn't have been any.

O-rings and gaskets should be still available for your sand filter. If you need to "re-fresh" your filter, unscrew the lid, and mix up the sand a bit (you can also take some sand out, and replace with new sand). Mix it up well, as sometimes the water finds shortcuts through the sand.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D